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Science China Chemistry 2009年第10期52卷 1583-1589页

作者： CHEN ShuJian glenn p.a.yap XUE ZiLing Department of Chemistry The University of TennesseeKnoxvilleTN 37996-1600USA Department of Chemistry&Biochemistry The University of DelawareNewarkDelaware 19716USA

Reaction of TaCl(NMe2)4 (1) with KTp* [Tp* = tris(3,5-dimethylpyrazolyl)borohydride] yields two products: Tp*Ta(NMe2)4 (2), in which one N atom of the Tp* ligand binds to Ta, and [Tp*Ta(NMe2)4]· 2KTp* (3) where three N atoms of the Tp* ligand in [Tp*Ta(NMe2)4] (2a) bind to Ta. Addition of excess 1 to 3 did not exclude KTp*. Further reaction of 2 with oxygen affords Tp*BH(NMe2) (4). TpTa(NMe2)4 (5) has been synthesized by a similar procedure through the reaction of 1 with TpK [Tp=tris(pyrazolyl)borohydride]. Reactions of 3 and 5 with oxygen were also studied. 2, 4, and 5 were characterized by NMR, EA, and single-crystal X-ray diffraction.

关键词： polypyrazolyborate tantalum amide oxygen

聚(吡唑)硼酸基-氨基钽化合物的合成、表征及和氧气的反应性

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中国科学（B辑） 2009年第10期39卷 1145-1152页

作者：陈树建 glenn p.a.yap 薛子陵 Department of Chemistry The University of Tennessee Department of Chemistry & Biochemistry The University of Delaware

TaCl(NMe2)4(1)与Tp*K[Tp*=三(3,5-二甲基吡唑)硼化氢]的反应给出两个产物:第一个产物是Tp*Ta(NMe2)4(2),其中Tp*配体的一个N原子跟钽配位成键;第二种产物是[Tp*Ta(NMe2)4]·2Tp*K(3),其中[Tp*Ta(NMe2)4](2a)的Tp*配体的三个N原子跟钽配位成键.过量的化合物1加入化合物3中并没有跟其中的Tp*K反应.化合物2与氧气的进一步反应给出产物Tp*BH(NMe2)(4).通过类似的方法,化合物1与TpK[Tp=三(吡唑)硼化氢]的反应产出化合物TpTa(NMe2)4(5).研究了化合物3和5与氧气的反应.用核磁共振,元素分析和单晶X射线衍射对化合物2,4,和5进行了表征.

关键词：聚吡唑硼基钽氨基氧气

Immunosuppressive,antimicrobial and insecticidal activities of inhibitor cystine knot peptides produced by teratocytes of the endoparasitoid wasp Cotesia flavipes(Hymenoptera:Braconidae)

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Insect Science 2023年第4期30卷 1105-1117页

作者： Ciro p.G.pinto Andrew A.Walker glenn F.King Guilherme D.Rossi School of Agricultural and Veterinarian Sciences Sao Paulo State University(UNESP)JaboticabalBrazil Institute for Molecular Bioscience The University of QueenslandSt LuciaBrisbaneQueenslandAustralia Australian Research Council Centre of Excellence for Innovations in peptide and protein Science The University of QueenslandQueenslandSt LuciaAustralia

Teratocytes are specialized cells released by parasitoid wasps into their *** are known for producing regulatory molecules that aid the development of imma-ture *** have recently reported the primary structures of cystine-rich peptides,including some containing inhibitor cystine knot(ICK)motifs,produced by teratocytes of the parasitoid Cotesia flavipes(Hymenoptera:Braconidae).ICKs are known for their stability and diverse biological *** this study,we produced four putative ICK peptides from the teratocytes of *** using solid-phase peptide synthesis or recom-binant expression in ***,and investigated their functions on host immune modulation as well their potential to impair the development of two lepidopterans after ingestion of the *** addition,the peptides were assayed against pathogens and human *** peptides did not influence total hemocyte count but suppressed cellular immunity,detectable as a reduction of hemocyte encapsulation(CtICK-I,CftICK-II,CtICK-I)and spread indexes(CftICK-IV)in the *** of the peptides influenced the activi-ties of prophenoloxidase and phenoloxidase in the hemolymph of larval Diatraea sacchar-alis(Lepidoptera:Crambidae).CftICK-I and CftICK-II with previously unknown function showed antifungal activity against Candida albicans but were non-toxic to human ***-I,CftICK-II,and CftICK-II increased larval mortality and reduced leaf consump-tion of ***,a permissive host for *** CftICK-III also increased larval mortality and reduced leaf consumption of Spodoptera frugiperda(Lepidoptera:Noctuidae),a non-permissive host for *** study highlights biological func-tions and biotechnological potential of ICK peptides from the teratocytes of ***.

关键词： biocontrol encapsulation host regulation Hymenoptera parasitoid phe-noloxidase

Assessment of micronucleus frequency in exfoliated buccal epithelial cells among fisher folks exposed to mine tailings in Marinduque Island,philippines

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Asian pacific Journal of Tropical Medicine 2010年第4期3卷 315-317页

作者： Elena M Ragragio Celeste p Belleza Mark C Narciso glenn L Sia Su Biology Department University of the Philippines-ManilaManilaPhilippines Biology Department De La Salle UniversityManilaPhilippines

Objective:To evaluate the potential toxic effects of mine tailings exposure among the fisher folks residing near and far from the Calancan Bay,Marinduque,using the micronucleus assay as an ***:The fisher folks residing near and far from the Calancan Bay were interviewed and the presence and frequency of cells with micronucleus in exfoliated buccal epithelial cells were ***:Results showed that the prevalence of cells with micronucleus was higher among the fisher folks who were directly exposed to the mine tailings as compared with those fisher folks who reside in a community without exposure of mine tailings and history of mining(ppresence and the significant difference in the cells with micronuclei observed near the Calancan Bay could possibly indicate a prolonged chemical stress caused by the toxic heavy metals in the mine tailings and the environment.

关键词： Micronuleus frequency Epithelial cells Fisher folks

B lymphocytes regulate airway granulocytic inflammation and cytokine production in a murine model of fungal allergic asthma

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Cellular & Molecular Immunology 2015年第2期12卷 202-212页

作者： Sumit Ghosh Scott A Hoselton Scott V Asbach Breanne N Steffan Steve B Wanjara glenn p Dorsam Jane M Schuh Department of Veterinary and Microbiological Sciences North Dakota State University Fargo ND USA

Sensitization to fungi often leads to a severe form of asthma that is particularly difficult to manage clinically, resulting in increased morbidity and hospitalizations in these patients. Although B lymphocytes might exacerbate asthma symptoms through the production of IgE, these cells might also be important in the protective response against inhaled fungi. Through cytokine release and T-cell interactions, these lymphocytes might also influence the development and maintenance of airway wall fibrosis. JH-/- mice lack the JHgene for the heavy chain component of antibodies, which is critical for B-cell function and survival. These animals have facilitated the elucidation of the role of B iymphocytes in a number of immune responses; however, JH-/- mice have not been used to study fungal allergy. In this study, we examined the role of B lymphocytes using an Aspergillus fumigatus murine fungal aeroallergen model that mimics human airway disease that is triggered by environmental fungal exposure. We compared disease progression in sensitized wild-type BALB/c and JH-/- mice that were exposed to repeated fungal exposure and found no differences in airway hyperresponsiveness, overall pulmonary inflammation or collagen deposition around the large airways. However, the levels of the Th2-type cytokines IL-4 and IL-13 were significantly attenuated in the airways of JH-/- mice relative to the BALB/c controls. By contrast, levels of the inflammatory cytokines IL-17A and IL-6 were significantly elevated in the JH-/- animals, and there was significantly more robust airway eosinophilia and neutrophilia than in control animals. Taken together, these findings demonstrate that B lymphocytes help to regulate granulocytic responses to fungal exDosure in the pulmonary compartment.

关键词： Aspergillus fumigatus B lymphocytes inflammation

Study of Wear in a Novel Cu-Based Sintered Alloy for Train Brakes (Influence of Sintered Temperature)

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Study of Wear in a Novel Cu-Based Sintered Alloy for Train B...

作者： glenn Kwabena Gyimah 华南理工大学

学位级别：硕士

A novel Cu-based composite frictional train brake material composed of several elements such as Al, SiO2, Fe, graphite, Sn, Mn and MoS2 re-enforced with other elements was treated under powder Metallurgy （p/M） route. Well prepared powders were hydraulically compacted at 650Mpa. The materials were sintered at three different temperatures （850oC, 900oC and 950oC） at a constant pressure. The dry sliding friction and wear characteristics of three different sintering treatment temperatures were investigated and the results were remarkable. The tribological behavior of these materials was analyzed by pad-on-disk tests without lubrication and the coefficient of friction, wear rate and wear number were studied in order to identify the effects of the sintering temperature on the base materials composition. The porosities were found to be very high but were adequate to give the right self lubrication properties and to reduce seizure. It was found that the porosity varies inversely proportional to the increase in sintering temperature. The pores in the sintered material were mainly solid lubricants such as graphite and other low melting elements. This also resulted in poor hardness and mechanical properties, which were compensated by its ability to reduce seizure. Much lower wear frictional coefficient, k and the highest coefficient friction,μwith a high wear number, Wn were obtained, indicating a good wear resistance property of the friction material. Three forms of wear mechanisms were observed during the dry sliding process, namely;delamination wear, plowing wear and abrasive wear. The abrasive wear results in flake or break-away debris. These wear mechanisms were found to be responsible for high wear rates on samples sintered at 850oC and 900oC. Generally, the materials demonstrated excellent brake performance and wear resistance. The average values of friction coefficient under excessive pressure （3.13Mpa） dry conditions were 0.336, 0.343, and 0.404, at 850oC, 9

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Gp prescribing in Northern Ireland by deprivation index:retrospective analysis

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Family Medicine and Community Health 2020年第3期8卷 18-26页

作者： John Scott Frazer glenn Ross Frazer Somerville College University of OxfordOxfordUK School of Mathematics and physics Queen's University BelfastBelfastUK

Objective In the present study,we sought to explore the relationship between socioeconomic status and prescribing magnitude and cost in primary care throughout Northern *** We performed a retrospective data analysis of general practitioner(Gp)prescribing using open-source databases with data collected from May to October 2019 to determine the number of prescriptions and cost of drugs and drug classes by area,ranking these by deprivation *** used Kendall’s tau to quantify the relationship between prescribing and *** We analysed open-source data collected from 325 Gp practices in Northern Ireland during the period from May to October *** We analysed a total of 2764303 prescriptions signed during our study *** Our study indicates a clear trend of increased overall spending per patient(r=−0.1232,p=0.02)and number of prescriptions per patient(r=−0.3440,pper item was higher in less deprived areas(r=0.3809,ppent and 3.5 more items were prescribed per patient in the most compared with the least deprived decile,although more expensive items tended to be prescribed in areas with lower socioeconomic deprivation(£11.27 per item vs£9.20 per item).We found a statistically significant correlation of prescribing of key drug classes,such as bronchodilators,antidepressants and drugs used to treat diabetes,among others,with greater *** of vaccines and drugs used in the treatment of glaucoma was correlated with lower *** We provide an exploration of the correlation of prescribing with deprivation by analysing all prescriptions signed within a 6-month period in Northern *** study broadly agrees with published literature,although a few notable exceptions are *** provide evidence of discrepancies in medication cost between areas of differing deprivation and suggest possible explanations for t

关键词： prescription drugs prescribed

prevalence of intestinal parasites in selected vegetables at major public markets in Metro Manila,philippines

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Asian pacific Journal of Tropical Medicine 2009年第6期2卷 37-39页

作者： Malison Marilyn T Sia Su glenn L pamantasan ng Lungsod ng Maynila ManilaPhilippines School of Environmental Science and Management University of the Philippines Los BanosLagunaPhilippines

Objective:This study aims to determine the prevalence of intestinal parasites infesting the vegetable foodstuffs and determine the parasitological profile of the vegetable foodstuffs ***:About 200 randomly sampled vegetable foodstuffs obtained from the vendors of the Balintawak and Divisoria public markets were examined for the occurrence of intestinal ***:A total of 119(59.5%) vegetable foodstuffs examined were tested *** most common parasite found was the Ascaris *** significant differences between the prevalence of intestinal parasites at the two public markets were found(p > 0.05).Conclusion: The vegetables can be a potential source of parasitic infection.

关键词： parasite Vegetable Foodstuff Intestinal parasite public market

Synsepalum dulcificum extracts exhibit cytotoxic activity on human colorectal cancer cells and upregulate c-fos and c-jun early apoptotic gene expression

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Asian pacific Journal of Tropical Biomedicine 2018年第3期8卷 173-178页

作者： Jichang Seong glenn G.Oyong Esperanza C.Cabrera Biology Department De La Salle University Molecular Science Unit Laboratory Center for Natural Science and Environmental Research De La Salle University

Objective: To explore cytotoxicity of Synsepalum dulcificum(S. dulcificum) Daniell(Sapotaceae) on human colon cancer(HCT-116 and HT-29), human monocytic leukemia(THp-1) and normal(HDFn) cell lines, and its effect on the expression of early apoptotic genes, c-fos and c-jun. Methods: Leaf, stem and berry of S. dulcificum were separately extracted by using 2 solvents, 10% ethanol(EtOH) and 80% methanol(MeOH). prestoB lue~? cell viability assay and q RT-pCR assay were conducted to examine the above objectives respectively. Results: Stem MeOH, stem EtOH, and berry EtOH extracts of S. dulcificum were cytotoxic to HCT-116 and HT-29 human colon cancer cells. For HCT-116, IC_(50) values of these 3 extracts were not significantly different(p>0.05) from that of the positive control bleomycin(IC_(50) of 33.57 μg/mL), while for HT-29, IC_(50) values of these 3 extracts were significantly lower(pp-1 monocytic leukemia cells and HDFn normal human dermal fibroblasts. For both HCT-116 and HT-29, these extracts significantly up-regulated(ppression of c-fos and c-jun compared to the untreated negative control. Conclusions: The results of this study suggest that cytotoxicity of stem MeOH, stem EtOH, and berry EtOH extracts of S. dulcificum on HCT-116 and HT-29 colon cancer cells is due to the induced apoptosis which is caused by the up-regulation of the expression of early apoptotic genes, c-fos and c-jun.

关键词： Synsepalum dulcificum Colon cancer Monocytic leukemia Apoptosis c-fos c-jun

Combined influence of Ce(Ⅲ)and iodide ions for corrosion protection of AA 2024-T3 in acidic to neutral chloride-rich environments:Electrochemical and surface characterization studies

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Journal of Rare Earths 2023年第2期41卷 309-320页

作者： Mohammed A.El-Hashemy Anthony E.Hughes Thomas Gengenbach A.Matthew glenn Ivan S.Cole Chemistry Department College of ScienceJouf UniversityP.O.Box 2014SakakaAljoufSaudi Arabia Air pollution Research Department Environmental and Climate Change Research InstituteNational Research CentreDokkiGiza12622Egypt CSIRO Mineral Resources ClaytonVic3168Australia CSIRO Manufacturing ClaytonVic3168Australia School of Engineering RMIT UniversityCarltonVic3053Australia

It has been reported that trivalent cerium salts are effective inhibitors for corrosion of AA2024-T3 in neutral to alkaline co rrosive enviro nments,but poor in acidic *** this study,work was done for extending corrosion resistance provided by Ce(NO_(3))_(3)to acidic pHs as low as 2.5 through the addition of iodide *** this end,potentiodynamic polarization was used to ascertain the optimum Ce(Ⅲ)concentration for the inhibition of AA2024-T3 corrosion in 3.5%NaCl *** optimum concentration is found to be in a range between 0.1 and 0.3 mmol/L Ce(Ⅲ).This optimum concentration also gives a maximum width of the passive region under the pitting potential(Epit).Based on this optimization,further work was performed as a function of pH without and in the presence of 0.01 mol/L KI at five pH values(2.5,4,5,7,and 8).Without iodide the best inhibition provided by the Ce(Ⅲ)cation is at pH=7 but active corrosion is observed at pH=2.5 with an estimated inhibitor efficiency(-37.6%).The addition of iodide ions(I^(-))reverses the poor corrosion resistance whereby the inhibitor efficiency becomes 47.7%.Moreover,at pH=4 the efficiency is also increased from 54.0%to 81.0%with iodide addition providing a significant improvement over Ce(Ⅲ)cations alone under acidic *** is a synergistic effect between I-anion and Ce(Ⅲ)cation,which is determined to be 2.4 and 2.1 at pH=2.5and 4.0,*** pH=5 and 7 there is virtually no change in inhibition but at pH=8 the inhibition falls away due to a considerable amount of cerium precipitating out of solution as cerium *** protective film formed on sites in the aluminium alloy surface at different pH values was examined by both scanning electron microscopy with energy dispersive X-ray analysis and X-ray photoelectron spectroscopy to determine the role of these ions as a function of pH in surface *** is proposed that at pH=2.5 protection is provided by a bilayer adsorption of iodide with"cap

关键词： Aluminium alloy Cerium(Ⅲ)salt potassium iodide Corrosion inhibitor XpS Rare earths